// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_BROWSER_BROWSER_URL_HANDLER_IMPL_H_
#define CONTENT_BROWSER_BROWSER_URL_HANDLER_IMPL_H_

#include <utility>
#include <vector>

#include "base/gtest_prod_util.h"
#include "base/macros.h"
#include "base/memory/singleton.h"
#include "content/public/browser/browser_url_handler.h"

class GURL;

namespace content {
class BrowserContext;

class CONTENT_EXPORT BrowserURLHandlerImpl : public BrowserURLHandler {
public:
    // Returns the singleton instance.
    static BrowserURLHandlerImpl* GetInstance();

    // BrowserURLHandler implementation:
    void RewriteURLIfNecessary(GURL* url,
        BrowserContext* browser_context,
        bool* reverse_on_redirect) override;
    void SetFixupHandler(URLHandler handler) override;
    // Add the specified handler pair to the list of URL handlers.
    void AddHandlerPair(URLHandler handler, URLHandler reverse_handler) override;

    // Fixes up the URL before rewriting occurs.
    void FixupURLBeforeRewrite(GURL* url, BrowserContext* browser_context);

    // Reverses the rewriting that was done for |original| using the new |url|.
    bool ReverseURLRewrite(GURL* url, const GURL& original,
        BrowserContext* browser_context);

private:
    // This object is a singleton:
    BrowserURLHandlerImpl();
    ~BrowserURLHandlerImpl() override;
    friend struct base::DefaultSingletonTraits<BrowserURLHandlerImpl>;

    // A URLHandler to run in a preliminary phase, before rewriting is done.
    URLHandler fixup_handler_;

    // The list of known URLHandlers, optionally with reverse-rewriters.
    typedef std::pair<URLHandler, URLHandler> HandlerPair;
    std::vector<HandlerPair> url_handlers_;

    FRIEND_TEST_ALL_PREFIXES(BrowserURLHandlerImplTest, BasicRewriteAndReverse);
    FRIEND_TEST_ALL_PREFIXES(BrowserURLHandlerImplTest, NullHandlerReverse);
    FRIEND_TEST_ALL_PREFIXES(BrowserURLHandlerImplTest, ViewSourceReverse);

    DISALLOW_COPY_AND_ASSIGN(BrowserURLHandlerImpl);
};

} // namespace content

#endif // CONTENT_BROWSER_BROWSER_URL_HANDLER_IMPL_H_
